1. Field of the Invention
The invention relates to a carrier on a computer server for an expansion card and a method for assembling the same.
2. Background Art
An expansion card is a circuit board which is designed to extend or supplement the functionality of a mainboard in a computer. Sometimes, it is also used to modify and update the basic functionality of a mainboard. For example, when new features for a processor in a mainboard are developed, it could be advantageous in cost and time to plug an expansion card containing the newly developed features into a special port or connector on the mainboard rather than to completely re-design the previous processor.
As an example of such an expansion card, there is Advanced Mezzanine Card in the pertinent art, which can be abbreviated as AdvancedMC or AMC. Advanced Mezzanine Card is a printed circuit board (PCB) that follows the specifications of the PCI Industrial Computers Manufacturers Group (PICMG). Advanced Mezzanine Card, which meets the PICMG industrial standards, can be used as an expansion card to provide extended functionalities such as DSP and network communications to a blade server. A blade server is ideal for specific purposes such as web hosting and cluster computing.
A blade server is designed to have a chassis for housing a number of individual circuit boards, each having one or more processors, memory, storage, and network connections, but sharing, for example, a power supply and air-cooling resources (e.g., fans) of the chassis. Those skilled in the art will recognize that one of the aims in using a blade server is to be able to place many blades in a single chassis, thereby compacting increased computing power in an area less than that which would be necessary were each of the blades individually housed.
Because such a blade server aims to provide fundamental computing functions with space-efficiency, an expansion card may sometimes be needed, for example, to supplement storage, network connectivity, and image and sound information processing performance. An expansion card is typically added to a computer after being accommodated in a carrier and plugged into a connector. An expansion card carrier retains an expansion card inside and keeps the expansion card electrically connected to a socket in the connector.
FIG. 1A illustrates a conventional expansion card assembly 100. Typically, expansion card assembly 100 is inserted in the longitudinal direction into an expansion card carrier (not shown). An expansion card 130 can may contain necessary circuitry such as arithmetic processors, information processing units, and network communication processors.
A pin array 135 is provided along the rear edge of expansion card 130. Pin array 135 can be electrically mated with a connector (not shown) on a mainboard of a computer upon insertion. A handle 110 is a leverage which can help a user grab, move, insert, or remove expansion card assembly 100. On a faceplate 120, indicators such as LEDs and labels may be provided for users' convenience.
Referring next to FIG. 1B, three expansion card assemblies 102, 104, 106 are inserted into an expansion card carrier 105. The left two of expansion card assemblies 102, 104 are single-width expansion card assemblies whereas the rightmost expansion card assembly 106 is a double-width expansion card assembly. As can be seen in FIG. 1B, expansion card assembly 106 is twice the size of expansion card assemblies 102, 104. An ejecting mechanism 170 functions to lock the inserted expansion card assemblies to carrier 105 and, after use, to help the expansion card assembly easily to be released from carrier 105.
FIG. 2A is a perspective view of an exploded expansion card carrier 205 in the prior art. A covering panel 210 covers the entire carrier from the top. Card guides 250 have a groove 251 which can guide an expansion card (not shown) to be inserted into the proper position of carrier 205 and to be mated appropriately with a connector 294. On upper portions of card guides 250, protruding tabs 254 are formed to make card guides 250 secured to covering panel 210. Receptacles 214 in covering panel 210 are dimensioned to accept and latch protruding tabs 254 so that card guides 250 can be fixed to covering panel 210. Struts 257 support card guides 250 and covering panel 210 on a bottom panel 220.
FIG. 2B illustrates a card guide in further detail. In this type of card guide 255, two grooves 257, 259 are formed to accept and retain two expansion cards. Protruding tabs 254′ provides a fastening mechanism as explained with reference to FIG. 2A. A strut 258′ is a means for supporting card guide 255 on a bottom panel. In addition, strut 258′ is used as a means for supporting a cover panel on a bottom panel in the same manner as explained referring to FIG. 2A.